elektronika cyfrowa

Intermediate bombarding energies
before
after
TLF
midcentral
IVS
PLF
central
CS
PEP
IVS –Intermediate Velocity Source
PEP –Promt Emitted Particles
Time evolution of 124Sn+64Ni reaction
at 35 MeV/nucleon
QMD predictions
CHIMERA code
J.Lukasik
gg
gg
gg
ggfm/c
Linear momentum transfer measurements
Factor  LMT , a measure of LMT, is defined as:

LMT

p par
pp
- p par is a parallel component (to the beam direction) of the linear
momentum transferred to the quasi-compound nucleus.
- p p is the projectile linear momentum.
Velocity spectra of
evaporation residues (ER)
suggesting that the lighter
nucleus loses momentum
(mass). Fits are
calculations with Gaussian
function. The quoted
numbers indicate the
fraction of complete fusion
(dashed curves).
Ar
C
𝑽 > 𝑽𝑪𝑵
Ne
𝑽 < 𝑽𝑪𝑵
Al
As can be seen it is striking that:
mass symmetry in the entrance channel leads
to mean ER velocities  R =  CN ;
 mass asymmetry for a light projectile and a heavy target leads
to R < CN and in the oposite case we have R >  CN

v3
3
 fold

v4

vR
 CM
v3
 CM
v4
Folding angle,  fold, between the two fission fragments.
VR is the velocity of the quasi-compound nucleus.
The relationship between fold and LMT
:

LMT

A44 sin  fold
A 1 1 sin  3
where A1, v1 are the mass and velocity of the
projectile, A4, 4 those of one of the fission
fragments before evaporation.
The relationship between fold and LMT :
 fold
LMT → 0
↔
fold → 180 degrees
Fission fragment folding angle distribution for 14N +238U reaction.
For each measurement a linear momentum transfer scale,  LMT , is
shown immediately above the data.
Two remarks may be stressed:
 the central collision bump exists for any bombarding energy up to
45 MeV/nucleon
 the LMT is complete up to 10 - 15 MeV/nucleon and is more and
more incomplete above.
Inclusive fission
fragment folding
angle distributions
for Ar + Th
reactions from 15 to
115 MeV/nucleon.
Fission fragment folding
angle distributions for Ar +
Th reactions
• gated on IMFs at forward
angles (left column),
•IMFs at large angle (center
column),
•and central collision
impact parameter obtained
by the total transverse
kinetic energy.
Solid lines are Gaussian
to guide the eye.
IMF
FF1
IMF
FF2
IMF – Intermediate Mass Fragment
FF- FissionFragment
The rel is defined as:
 rel 
2 ECM  VC 

where ECM is the center of mass energy,
VC the Coulomb barrier and  the reduced
mass.
Most probable
values of LMT
measured in
various reactions
as a function of
the relative
velocity of the
incoming ions.
The line
corresponds to the
fit.
INDRA AT GANIL, FRANCE
Isotopic resolution
Charity evaporation attractor line
N/Z of system (1.07)
Z≤4
5≤Z≤24
Z≥25
Plastics (phoswichs)
Ionisation chambers
Silicons
CsI (Tl)
target
beam
CHIMERA
Charged Heavy Ion Mass and Energy Resolving Array
Istituto Nazionale di Fisica Nucleare Laboratori Nazionali del Sud
• 35 rings
• 1192 telescopes Si-CsI
• 1 °    176 °
• Identifications: 3 methods
 E-ΔE, TOF, PSD
Experimental methods
CsI(Tl)
6He
4He
Li
H.I.
3He
t
Si
d
p
PSD
ΔE-TOF
M,E
DE-E
LCP
Z, E
http://fazia.in2p3.fr
GANIL/SPIRAL/SPIRAL2 Caen
GSI/FAIR/NUSTAR Darmstadt
LNL/ALPI/SPES Legnaro
LNS/EXCYT/FRIBS Catania
2012-2015
10 240 x 3
detektorów
FIZYKA - GLOBALNE WŁASNOŚCI
MATERII JĄDROWEJ (MJ)
TECHNOLOGIE CYFROWE
ULTRASZYBKA ELEKTRONIKA CYFROWA
TERMODYNAMIKA MJ
ASIC
RÓWNANIE STANU MJ (NEOS)
DETEKTORY MONOLITYCZNE
ASTROFIZYKA JĄDROWA
DIGITALIZACJA SYGNAŁU (2 Gs/s, 14 bit)
ANALIZA KSZTAŁTU IMPULSU
TESTY MODELU STANDARDOWEGO
MATEMATYCZNE ALGORYTMY
,
IDENTYFIKACYJNE
FUNDAMENTALNE SYMETRIE
21
Tomasz Kozik
,
22